Portion-control dishes may help obese diabetics lose weight

June 25, 2007

A plate and cereal bowl with markers for proper portion sizes appear to help obese patients with diabetes lose weight and decrease their use of glucose-controlling medications, according to a report in the June 25 issue of Archives of Internal Medicine, one of the JAMA/Archives journals.

Between 1960 and 2000, the proportion of U.S. adults who were obese increased from 13.4 percent to 30.9 percent, according to background information in the article. Most cases of type 2 diabetes can be attributed directly to obesity. Restricting calories has been shown to improve blood sugar control in diabetics, partially by contributing to weight loss. “The increasing prevalence of obesity is paralleled by increasing portion sizes in the marketplace,” the authors write. “Portion sizes are an important determinant of energy intake; the number of calories ingested by subjects at a meal has been directly correlated with the serving size offered.”

Sue D. Pedersen, M.D., F.R.C.P.C., and colleagues at the University of Calgary, Alberta, Canada, conducted a six-month controlled trial of commercially available portion control plates and bowls in 2004. The plates were divided into sections for carbohydrates, proteins, cheese and sauce, with the rest left open for vegetables. The sections approximately totaled an 800-calorie meal for men and a 650-calorie meal for women. The cereal bowl is designed to allow a 200-calorie meal of cereal and milk. Half of 130 obese patients with diabetes (average age 56) were randomly assigned to use the plate for their largest meal and the bowl when they ate cereal for breakfast. The other half of the participants received usual care, which consisted of dietary assessment and teaching by dieticians.

At the end of the six-month follow-up, 122 patients remained in the study. Individuals using the portion-control dishes lost an average of 1.8 percent of their body weight, while those receiving usual care lost an average of 0.1 percent. A significantly larger proportion of those using the dishes—16.9 percent vs. 4.6 percent—lost at least 5 percent of their body weight. “This is important, as a 5 percent weight loss has been shown to be clinically significant in terms of decreasing morbidity and mortality associated with obesity-linked disorders such as cancer and myocardial infarction [heart attack],” the authors write.

In addition, more of those in the intervention group vs. the regular care group experienced a decrease in their use of diabetes medications after six months (26.2 percent vs. 10.8 percent).

Source: JAMA and Archives Journals